"…exposure to increased amounts of lead and fluoride occurs at about the
same age (1-3 years)… Therefore, this is a critical time when systemic
exposure to fluoride should be minimized since fluoride may increase lead
accumulation," the researchers caution.

Low-level lead exposure is associated with lower IQ, ADHD and many
health and behavior ailments.

Fluosilicic acid (fluoride) is added to water supplies ostensibly to reduce
tooth decay.

Sawan's team put fluosilicic acid, with and without lead, into lab animals'
drinking water. They found more lead in tooth enamel, surface bone, whole
bone, and tooth dentin in rats co-exposed to fluoride and lead.

Possibly anticipating criticism that rats were fed higher fluoride-concentrated
water than people drink, the authors write, "This concentration was chosen
because it produces plasma fluoride levels that are comparable with those
commonly found in humans…"

Increased prevalence and severity of fluoride-discolored teeth (fluorosis)
proves U.S. children are already fluoride-overexposed, "which may cause
their blood-lead levels to increase and produce more lead toxicity," they write.

"These findings suggest that a biological effect, not recognized so far, may
underlie the epidemiological association between increased blood-lead l
evels in children and water fluoridation," concludes Sawan's research team.

"[O]ur findings may have serious implications for populations exposed to
increased amounts of both lead and fluoride, particularly young children,"
the research team writes.